diff --git a/piet-gpu/bin/winit.rs b/piet-gpu/bin/winit.rs
index c5f9bef..19db3c2 100644
--- a/piet-gpu/bin/winit.rs
+++ b/piet-gpu/bin/winit.rs
@@ -1,4 +1,3 @@
-use piet::RenderContext;
 use piet_gpu_hal::{Error, ImageLayout, Instance, Session, SubmittedCmdBuf};
 
 use piet_gpu::{test_scenes, PietGpuRenderContext, Renderer};
@@ -152,6 +151,13 @@ fn main() -> Result<(), Error> {
 
                     current_frame += 1;
                 }
+                Event::LoopDestroyed => {
+                    if let Some(submitted) = submitted.take() {
+                        // Wait for command list submission, otherwise dropping of renderer may
+                        // cause validation errors (and possibly crashes).
+                        submitted.wait().unwrap();
+                    }
+                }
                 _ => (),
             }
         })